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Acta Cryst. (2014). A70, C347
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Molecular Replacement (MR) is an increasingly popular route to protein structure solution. AMPLE[1] is a software pipeline that uses either cheaply obtained ab inito protein models, or NMR structures to extend the scope of MR, allowing it to solve entirely novel protein structures in a completely automated pipeline on a standard desktop computer. AMPLE employs a cluster-and-truncate approach, combined with multiple modes of side chain treatment, to analyse the candidate models and extract the consensual features most likely to solve the structure. The search models generated in this way are screened by MrBump using Phaser and Molrep and correct solutions are detected using main chain tracing and phase modification with Shelxe. AMPLE proved capable of processing rapidly obtained ab initio structure predictions into successful search models and more recently proved effective in assembling NMR structures for MR[2]. Coiled-coil proteins are a distinct class of protein fold whose structure solution by MR is not typically straightforward. We show here that AMPLE can quickly and routinely solve most coiled-coil structures using ab initio predictions from Rosetta. The predictions are generally not globally accurate, but by encompassing different degrees of truncation of clustered models, AMPLE succeeds by sampling across a range of search models. These sometimes succeed through capturing locally well-modelled conformations, but often simply contain small helical units. Remarkably, the latter regularly succeed despite out-of-register placement and poor MR statistics. We demonstrate that single structures derived from successful ensembles perform less well, and comparable ideal helices solve few targets. Thus, both modelling of distortions from ideal helical geometry and the ensemble nature of the search models contribute to success. AMPLE is a framework applicable to any set of input structures in which variability is correlated with inaccuracy. We also present preliminary data demonstrating structure solution of transmembrane helical structures using Rosetta modelling. We finally consider future sources of starting models which offer the hope that MR with AMPLE, in the absence of close homology between a known structure and the target, may soon be possible with larger proteins.

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Acta Cryst. (2014). A70, C781
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The CCP4 software suite [1] provides a comprehensive set of tools for use in the macromolecule structure solution process by X-ray crystallography. Traditionally, these tools have been run through the graphical interface or the command line on each user's personal workstation. Recently, some of the tools, including the molecular replacement pipelines Balbes [2] and MrBUMP [3] have been provided as web services in the Research Complex at Harwell. These pipelines can be especially useful in cases where there is low sequence identity between the target-structure sequence and that of its set of possible homologues. These services can be accessed through a web client, allowing one to submit molecular replacement jobs to our Linux cluster and view the results from these jobs. The molecular replacement pipelines are ideal candidates for web services, as they require installation and maintenance of large databases and benefit from parallel computing resources, provided by the cluster. Further plans for web services will be discussed. With ever-increasing mobility of scientific setups and the ubiquity of ultra-portable devices, there is a demand for a consistent framework of remote crystallographic computations and data maintenance. This framework is planned to include an interface for synchronising data with the facilities of Diamond Light Source, as well as with local CCP4 GUI-2 setups.

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Acta Cryst. (2014). A70, C1447
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"In 2013 MX beamlines at the Diamond synchrotron deployed an automated software pipeline, called DIMPLE, for rapid processing of crystals that contain a known protein and possibly a ligand bound. DIMPLE takes the already known ""apo"" structure for the target protein, compares it with the electron density map from X-ray diffraction images, and visualizes areas of the electron density unaccounted for by the structure model. When processing batches of crystals, such feedback allows the user to better decide what to measure next which leads to a more efficient use of the beam time. This year we've enhanced the pipeline to cover more complex cases, including changes in the space group and some changes in conformation. With multiple molecular replacement computations run in parallel, the time from shooting to viewing the difference map is still only a few minutes. While the software is developed primarily for use at synchrotron beamlines, it is included in the CCP4 suite and can be used as well for in-house automation."

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Acta Cryst. (2014). A70, C1723
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CCP4 has been serving the software needs of the protein crystallography community for more than 30 years. In this time the CCP4 Suite of software has been refined through contributions from some of the leading developers in the field of protein crystallographic software and the feedback of both expert and novice users. Today it is a highly comprehensive suite, providing tools and packages covering all aspects from data collection through to structure deposition. Here we will present details of the latest release series of the Suite, version 6.4. This release brings updates to many of the key elements in the Suite. The most obvious of these is the integration of the rolling updates mechanism. This is used to distribute timely fixes, update existing programs and introduce new functionality to users of the suite. Recent updates have seen updates to major programs such as phaser and imosflm/mosflm, and the introduction of a major overhaul of the Experimental Phasing pipeline Crank. An overview is given of the operation behind the updates and releases, including the jhbuild system, repositories and testing, the availability of nightly builds, and work towards the next major release of CCP4. This will see the integration of the CCP4MG package, along with preparations for the introduction of the long awaited CCP4i2.
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